MAX2172 Direct-Conversion to Low-IF Tuner for Digital Audio Broadcast
The MAX2172 direct-conversion to low-IF tuner is designed for digital audio broadcast (DAB) and terrestrial digital multimedia broadcast (T-DMB) applications, covering an input frequency range of 168MHz to 240MHz (VHF-III), 1452MHz to 1492MHz (L-band), and also 87MHz to 108MHz (FM). The MAX2172 achieves a high level of component integration, allowing lowpower, tuner-on-board designs. The direct-conversion to low-IF architecture eliminates the need for an IF-SAW filter while providing a balanced 2.048MHz center frequency baseband output to the demodulator.
The MAX2172 provides a buffered reference clock at the crystal frequency.
A sigma-delta fractional-N synthesizer is incorporated to optimize both close-in and wideband phase noise performances for OFDM applications where sensitivity to both 1kHz phase noise and wideband phase noise related to strong adjacents can be a problem.
The MAX2172 is available in a 40-pin thin QFN package (6mm x 6mm) with an exposed pad. Electrical performance is guaranteed over the extended -40°C to +85°C temperature range.
Applications/Uses
Fixed and Mobile Digital Audio Broadcast (DAB, DAB+) with FM
Terrestrial Digital Multimedia Broadcast (T-DMB) with FM
Functional Diagram
